多体量子纠缠与量子信息网络研究

项目名称： 多体量子纠缠与量子信息网络研究

项目编号： No.61475006

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 半导体科学、光学和光电子学

项目作者： 何琼毅

作者单位： 北京大学

项目金额： 85万元

中文摘要： 量子网络是指由量子传输通道和量子节点组成的复杂信息网络，它利用量子纠缠作为资源，遵循量子力学规律进行信息的运算、存储及传输。目前，基于两体纠缠的量子信息在理论和实验上都取得了丰硕的成果。随着实验成功制备多光子和多模光场纠缠态，多体纠缠已经成为一种重要资源，且在量子信息处理中有新的应用。申请人最近给出了一类具有EPR非定域性的真正多体纠缠的存在判据，利用该资源可以实现更安全、具有指向性的多方量子秘密共享方案。多体量子纠缠具有比两体纠缠更加丰富的纠缠结构和更为复杂的性质，在定性和定量的研究上都还处于探索阶段。本项目聚焦多体量子纠缠，针对多模连续变量光场以及冷原子与腔光力学杂化量子系统，采用超越平均场近似的方法，深入研究多体纠缠、特别是具有EPR非定域性的多体纠缠的判定、分类及度量问题，刻画热环境下多体量子系统的纠缠动力学行为，紧密结合实验，力争解释实验结果，并辅助实验设计多用户量子信息网络。

中文关键词： 量子纠缠；多体纠缠；量子非定域性；量子网络；纠缠动力学

英文摘要： Quantum information network refers to the information network consists of quantum transmission channels and quantum nodes, which follows the laws of quantum mechanics for information computation, storage, communication, and processing. Entanglement of two spacelike-separated systems is one of the most important features of quantum mechanics and is an essential resource for many existing quantum information experiments. Recent experimental realization of genuine multipartite continuous-variable entangled states and multiple-photon GHZ states, suggests a possibility to use the multipartite entanglement shared among all remote parties for multi-signature quantum information network. The applicant has developed the concept of genuine N-partite Einstein-Podolsky-Rosen (EPR) steering and its potential application in one-sided device-independent quantum secret sharing [PRL 111, 250403 (2013)], which has recently been realized experimentally by Lam's group in the Australian National University. Based on this work, this proposal focuses on developing (genuine) multimode quantum entanglement and EPR steering in many hybrid quantum atom-optomechanical nodes. This scheme paves an alternate route for a scalable quantum network. Using methods beyond the mean-field approximation, we aim at dynamic properties of the multipartite entanglement against the detrimental effects of the thermal environment. We also examine the quantum realm and the macroscopic classical world with increasing number of parties. In addition to giving insights into fundamental questions in physics, understanding and controlling (genuine) multipartite entanglement and steering in open systems may have strong implications in securer quantum communication or cryptography, quantum computing, quantum simulations of complex many-body systems,and quantum metrology. Research about this topic will be closely related to experimental progresses and assist experimental designs with multi-user quantum information network.

英文关键词： quantum entanglement;multipartite entanglement;quantum nonlocality;quantum network;dynamics